package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;
import org.springframework.util.StringUtils;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 拦截请求,必须登录后才可以访问资源
 */
@WebFilter(filterName = "LoginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //1、获取本次请求的URI
        String uri = request.getRequestURI();
        //定义不需要处理的请求路径
        String[] uris = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };
        //2、判断本次请求是否需要处理
        boolean check = check(uri, uris);
        //3、如果不需要处理，则直接放行
        if (check) {
            filterChain.doFilter(request, response);
            return;
        }
        //4、判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            /*在doFilter方法中, 判定用户是否登录,
             如果用户登录, 在放行之前, 获取HttpSession中的登录用户信息,
            调用BaseContext的setCurrentId方法将当前登录用户ID存入ThreadLocal。*/
            Long empid = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empid);

            filterChain.doFilter(request, response);
            return;
        }

        //4-2、判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("user") != null) {
            log.info("用户已登录，用户id为：{}", request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request, response);
            return;
        }

        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
//        /**
//         * 路径匹配，检查本次请求是否需要放行
//         * @param urls
//         * @param requestURI
//         * @return
//         */

    }

    private boolean check(String uri, String[] uris) {
        for (String s : uris) {
            boolean match = PATH_MATCHER.match(s, uri);
            if (match) {
                return true;
            }
        }
        return false;
    }


}
